Check
Request Games forum to see is the game already requested. If not, open new topic for each game you want to check status. Once request is approved (or if it already is), you are free to review it. Also, you might wanna search through
Submissions thread to check is the game perhaps already reviewed, but still not added to the site. That's about it.
You can review games that are rejected, but game won't be added to the site as long as it is protected. As for invalid requests, there is no need to review them.